Output control for accordions



March 1965 1. A. CARDOZA OUTPUT CONTROL FOR ACCORDIONS Filed April 9,1962 9 0 0 0 0 O 0 O O O0 O0 000 O OD O OO INVENTOR. I VING A. CHRDOZABY ,9 rrORNEY United States Patent Claims. (Cl. 84-376) The inventionrelates to the player control of an amplifying means for music beingproduced by an accordion, and this application comprises a substitutionfor the applicants application Ser. No. 742,296, filed June 16, 1958,now abandoned.

Understanding that the volume of musical sounds emitted from ahand-played accordion is limited by both the size of the sound chambersof the accordion and the applied energy of the player in operating thebellows, a primary general purpose of the present invention is toprovide a sound pick-up means for use with an electrically actuatedsound amplifier for providing the truest possible musical output of anaccordion at a controlled magnified volume and at a point remote fromthe accordion by a means under direct player control at the instrument.

Another object of the invention is to provide an amplifying device ofthe character described in which the relative amplified strengths of thenotes in the treble and bass ranges may be \adjustably varied by a meansat the instrument.

A further object is to provide for controlling the total volume of theamplified musical output by a means at the instrument.

An added object is to provide a coordinated tremolo control at theinstrument.

Yet another object is to provide all of the foregoing sound outputcontrols in connection with a unitary attachment for existing accordionstructures.

The invention possesses other objects and features of advantage, some ofwhich, with the foregoing, will be set forth or be apparent in thefollowing description of a typical embodiment thereof and in theaccompanying drawings, in which,

FIGURE 1 is a View showing the exterior of an accordion equipped with asound output control device embodying my invention.

FIGURE 2 is an enlarged and partly sectional longitudinal view throughthe device of my invention as applied to the accordion.

FIGURE 3 is a fragmentary section taken at the line 3-3 in FIGURE 2.

FIGURE 4 diagrammatically presents the essential control circuit of thepick-up and control elements of the device in combination with anassociated amplifier and speaker.

The features of my invention are particularly shown as associated withan accordion 6 of a usual type essentially having a treble body side orsection 7 provided with a keyboard of piano keys 8 and connected to abass side or section 9 provided with a bank of button keys It) by meansof a usual bellows 12. The instrument sections 7 and 9 are respectivelyprovided with usual soundbox cavities 13 and 14 respectively in whichthe sounds emitted from the diiierent sets of reeds (not shown)associated with the keys 3 and respectively are resonated for theirescape through sound-escape grilles provided by the respective sidestructures; the outer side 15 or" the present soundbox 13 of the treblesection 7 is provided with a suitable set of grille openings 16, landthe bass soundbox 14 has sound-escape grilles at its ends.

The various instrument-carried controls of my invention are particularlyshown as provided on, or in association with, a supplementary element 17which is mounted as an attachment for the treble section '7 in coveringrelation to the grille openings 16 thereof. The present element 17comprises an elongated body which is hollowed out from its inner side toprovide a relatively narrow elongated cavity 18 and is arranged for itsfixed disposal in covering opposition to the grille openings 16, saidcavity being defined by mutually coterminous side Walls 19 and end walls2-6 extending integrally from an outer and lingitudinally archedconnecting outer wall 21, with the walls 19 and 28 providing acontinuous fiat and rectangular edge face for engaging the outer face ofthe accordion body wall 15 about the grille portion thereof.

The element 17 is preferably releasably secured to the accordion bodysection 7 as an attachment therefor by means of screws which are tappedinto the body section 7 at the appropriately formed element ends 2t andmay engage a suitable sound insulation gasket between the member andbody, with the element preferably molded or otherwise formed of amaterial which is relatively nonresonant as compared with the generallyresonant and sound-conducting material of usual treble and bass sectionsof accordions. The outer wall 21 of the element 17 mounts the presentcircuit-control devices in the cavity 18, whereby the element therebyfunctions as a supporting housing for said devices.

It will now be noted that a microphone 24 is mounted on the outer wall21 of the control housing 17 Within the space 18, While a microphone 25is mounted in the soundbox 14 of the bass section 9, said microphonesbeing arranged to pick up the sounds respectively emanating from thetreble and bass soundboxes. In the case of the microphone 24, the sameis preferably located centrally of the longitudinally arched outerhousing wall 21, whereby the sound vibrations delivered into the space18 from the eble soundbox 13 through the grille openings 16 may bedelivered to this one treble pick-up microphone as a concentration ofthe different treble sound vibrations by wall reflection and airtransmission within the cavity 18. One terminal 24' of the microphone 24is connected to the terminal 26' of a resistor 26 mounted on the Wall 21and having a moving contact 27 carried by a control stem rotativelyextending through the housing wall 21 and carrying at its outer end apositioning turnbutton 28 providing a setting pointer 28' for use inadjusting the eliective resistance of the resistor by reference tosuitable calibration marks on the outer housing face thereat.

The wall 21 also mounts a resistor 29 disposed within the cavity 18 andhaving one terminal 29 thereof connected to a terminal 25' of themicrophone 25, said resister having a moving contact 31 carried by astern extending through the wall 21 and carrying a turnbutton 32providing a setting pointer 32. As indicated, the wire connections toand from the terminals 25' and 25" of the microphone 25 are convenientlyextended from the bass soundbox 14 through the bellows 12 and treblesoundbox 13 and through grille openings 16, and have extendable coilportions to provide for the required variable spacing of thebellows-connected instrument sections 7 and 9.

When the accordion is being played, the sound vibrations picked up bythe microphones 2d and 25 are arsauged to jointly produce acorresponding electric current in a common circuit for activating anamplifier-and-speaker assembly apart from the accordion and inaccordance with the adjusted resistances of the resistors 26 and 29.However, since it is preferable that the net volume of sound producedfrom the accordion be generally constant and controllable, a means isprovided in the housing 17 for automatically maintaining the soundoutput volume after the treble and bass outputs have been relativelyadjusted, said means essentially including a potentiometer 33 providedon the housing wall 21 within the space 18 same rs 3s and having itsmoving contact arm 3d mounted on a control stem which extends throughthe housing top 21 and mounts a turnbutton 35 providing a settingpointer 35'.

The present control unit also includes a switch 36 for controlling atremolo-producing circuit having its actuating means provided in unitaryassociation with the amplifier-speaker means to be controlled, wherebyto provide at the accordion all the controls customarily desirable inassociation with accordion-operated speakers. As indicated in FIGURE 4,the tremolo switch 36 comprises a movable contact arm 37 for engagementwith a fixed contact 38 for closing a circuit thereat, with said armcarried by a rotatable stem extending through the housing wall 21 andmounting a turnbutton 39 providing a pointer 39' for indicating theconditioning of the switch.

it will now be noted that the portion of the speakercontrolling circuitprovided on and in the accordion extends from the terminals of atriple-contact socket 41 provided in one end wall of the housing 17. Asis brought out in the diagrammatic showing of FIGURE 4, a conductor wire42 extends from a first contact of the connector 41 to a connection withthe second terminal 25" of the bass microphone 25 through a branch4-2-3, through a branch wire 42-2 to a terminal 24" of the treblemicrophone 24 and through a branch 423 to the contact 33 of thetremolo-control switch 36. Wires 43 and 44 respectively connect theother terminals 24' and 25' of the microphones 234 and 25 to theterminals 26' and 29' of the resistance elements of the resistors 29 and26 respectively, the movable contact arms 31 and 2'7 of said resistorsare connected by wires 45 and 46 to the different terminals of thearcuate resistance element of the potentiometer 33, and a second contactof the connector 41 is connected to the contact arm 34 of thepotentiometer 33 by a wire 4-7. The third contact of the socket 41 isconnected by a wire 48 to the switch arm 37 of the switch 36.

A three-wire extension cable provides wires 52 and 57 and 58 extendingfrom a plug 51 providing contact prongs which are respectivelyengageahle with the terminals of the wires 42 and 47 and 48 in theconnector socket 41 on the element 17. The present sound'amplifyingsystem essentially comprises an electronic amplifier 53 represented byits casing and receiving. power from the secondary of a transformer (notshown), and having its output connected to a speaker 55 by wires 56. Thewires 52 and 57 of the connected cable 56 lead from the wires 42 and 47in the socket 41 on the described accordion-carried pick-up and controlunit to the amplifier to provide for the amplification by the amplifier53 of the tonally adjusted output of the microphones for a broadcastdelivery of the musical output of the accordion in player-adjustedvolume and tone relations from the speaker 55, it being noted that theconnected wires 42 and 52 provide a common connection in the pick-up andtremolo circuits.

It will now be noted that the extension wire 58 leading from the socketterminal for the wire 48 of the circuit of the tremolo switch ascomprises a branch of one power input wire to the amplifier 53 and hasan electric motor 61 interposed therein for actuation when the tremolocontrol switch 36 at the accordion is closed. The shaft 62 of the motor61 carries a cam or eccentric 63 which is arranged to intermittentlyactuate a make-andbreak switch 64 having a spring-loaded switch armnoranally engaging a contact and arranged for its periodic displacementby the cam 63 to open the switch as the motor shaft 62 is rotated at apredetermined rotary speed. In this manner a manual closing of theswitch $6 of the present unitary pick-up attachment is arranged toautomatically produce a controlled tremolo effect in the output of thespeaker 55 whenever desired by the operator of the accordion, it beingunderstood that the tremolo-producing make-and-break action at themotoroperated switch 54 might be produced by some other means than thatdisclosed.

Although the described accordion-mounted controls might be provided in abuilt-in chamber of the accordion which corresponds to that of theunitary attachment element 7.7, the provision of the attachment as aseparate element is important for a number of reasons. Thus, the shapeof the chamber 18 may be that which is best for use with a particularaccordion to mount the unit and, what is more important, the resonantqualities of the material of the attachment are so much lower than thatof the accordion material which defines the soundbox cavities l3 and :14that the resonance effects of the original accordion structure are notmodified, while the picked up sounds for remote amplification may havetheir true tonal qualities and relations in a played musicalcomposition.

Experiment and experience have demonstrated that the design of thepresent unitary amplifying combination utilizing only a single pick-upmicrophone disposed adjacent a music source in a housing which isso-nally non-conductive has a number of marked practical advantages overthe known prior practice of using a common sound-conducting housing fera plurality of pick-up microphones. Thus, the present sonicallynon-conductive housing pre- Vents stray sounds from reaching the pick-upmicrophone and even permits a use of an accordion or similar instrumentimmediately adjacent the associated sound amplifier. On the other hand,the use of a single microphone from. a given resonance chamber or othersource disposed substantially at the geometric center, or centrally, ofthe housing cavity prevents the loss of sharpness of transmission due tothe fact that the sound waves from a single source cannot simultaneouslyreach all the microphones if a receiving set thereof is being used,whereby slurring distortion occurs from the resultant loss of phasecoincidence between the different microphones of a set which feeds agiven amplifier from the same resonance chamber. Accordingly, for theforegoing and other reasons, the operative arrangement and features ofthe present pick-up unit truly provide superior results in theamplifying of such musical sounds as those arising from the playing ofan accordion, for instance.

From the foregoing description taken in connection with the accompanyingdrawings, the advantages of the present output control for accordionswill be readily understood by those skilled in the art to which theinvention appertains. While I have shown and described a structure andarrangement which I now consider to be a preferred embodiment of myinvention, I desire to have it understood that the showings areprimarily illustrative, and that such changes and developments may bemade, when desired, as fall within the scope of the following claims:

1. In combination with a musical instrument having mutually independentresonance chambers for independently produced sound vibrations fromsonal vibrators within the different chambers, an electrically operativeaudio-amplifier means feedable by a common branched control circuitconductor having branches extending from within the different chambers,microphones associated with each said chambers for independentactivation by sound waves emanating from the sonal vibrators in thedifferent chambers to correspondingly energize different said branchesof said conductor, means in said circuit branches for independentlyadjusting the volumetric outputs of the different microphones thereto,and a potentiometer means carried by the instrument and variablycooperative between said branches of the control circuit for adjustmentby a player or" the instrument for inversely varying the volumetricratio of the combined microphone outputs delivered to theaudio-amplifier means through the potentiometer and the circuit of theconductor during a playing of the instrument.

2, In combination with a musicalinstrument having mutually independentresonance chambers for sound vibrations independently producible thereinby sonal vibrators and each provided with a sound-discharge opening, anelectrically operative audio-amplifier externally of the instrument andfeedable by branches of a common conductor extending from within theconfines of different chambers single and independently operativemicrophones unitarily associated with each of said chambers for theiractivation by sound Waves discharged through said charnber openings,with one said microphone disposed externally of the opening from thecorresponding resonance chamber and enclosed within a cavity provided byan instrument-mounted housing member of relatively nonresonanthomogeneous material having an open side sealediy fixed to the outerside of the outer wall of the resonance chamber to define therewith anotherwise closed sound-receiving cavity opposite said chamber opening,means mounting the enclosed said microphone centrally in said housingcavity, and a potentiometer means in said cavity providing connectionsof the different branches of said audio-amplifier control circuitconductor with the different said microphones.

3. The combination of claim 2 having a resistor means provided in eachbranch of the control circuit and disposed within the housing cavity foradjustment to independently adjust the volumetric outputs of theconnected different microphones, said potentiometer means being disposedWithin the housing cavity and directly cooperative between said controlcircuit branches and the said common conductor and is adjustable toadjust the volumetric ratio of the microphone outputs delivered to theaudio-amplifier means during a playing of the instrument.

4. In combination with a musical instrument having mutually independentresonance chambers for independently produced sound vibrations fromsonal vibrators within the diiferent chambers, an electrically operativeaudio-amplifier means feedable by a common control circuit conductorhaving branches extending thereto from the dilferent said chambers,microphones associated with the different said chambers and connectedwith the different said conductor branches for their independentactivation by sound waves emanating from the sonal vibrators in thediiferent chambers, and a potentiometer means connecting said circuitbranches to said conductor for adjustment by a player of the instrumentfor varying the volumetric ratio of the portions of the microphoneoutputs delivered from the potentiometer to the audio-amplifier meansthrough the circuit of the conductor during a playing of the instrument.

5. In combination with a musical instrument having mutually independentresonance chambers for independently produced sound vibrations fromsonal vibrators within the ditferent chambers, an electrically operativeaudio-amplifier means feedable by a common control circuit conductorhaving branches extending thereto from the different said chambers,microphones associated with the different said chambers and connectedwith the different said conductor branches for their independentactivation by sound Waves emanating from the sonal vibrators in thedifferent chambers, means for independently adjusting the volumetricoutputs of said microphones, and a potentiometer means connecting saidcircuit branches to said conductor for its adjustment by the player toinversely vary the portions of the outputs of the different microphonesdelivered by the potentiometer means to the audio-amplifier meansthrough the conductor circuit.

References Cited in the file of this patent UNITED STATES PATENTS

1. IN COMBINATION WITH A MUSICAL INSTRUMENT HAVING MUTUALLY INDEPENDENT RESONANCE CHAMBERS FOR INDEPENDENTLY PRODUCED SOUND VIBRATIONS FROM SONAL VIBRATORS WITHIN THE DIFFERENT CHAMBERS, AN ELECTRICALLY OPERATIVE AUDIO-AMPLIFIER MEANS FEEDABLE BY A COMMON BRANCHED CONTROL CIRCUIT CONDUCTOR HAVING BRANCHES EXTENDING FROM WITHIN THE DIFFERENT CHAMBERS, MICROPHONES ASSOCIATED WITH EACH SAID CHAMBERS FOR INDEPENDENT ACTIVATION BY SOUND WAVES EMANATING FROM THE SONAL VIBRATORS IN THE DIFFERENT CHAMBERS TO CORRESPONDINGLY ENERGIZE DIFFERENT SAID BRANCHES OF SAID CONDUCTOR, MEANS IN SAID CIRCUIT BRANCHES FOR INDEPENDENTLY ADJUSTING THE VOLUMETRIC OUTPUTS OF THE DIFFERENT MICROPHONES THERETO, AND A POTENTIOMETER MEANS CARRIED BY THE INSTRUMENT AND VARIABLY COOPERATIVE BETWEEN SAID BRANCHES OF THE CONTROL CIRCUIT FOR ADJUSTMENT BY A PLAYER OF THE INSTRUMENT FOR INVERSELY VARYING THE VOLUMETRIC RATIO OF THE COMBINED MICROPHONE OUTPUTS DELIVERED TO THE AUDIO-AMPLIFIER MEANS THROUGH THE POTENTIOMETER AND THE CIRCUIT OF THE CONDUCTOR DURING A PLAYING OF THE INSTRUMENT. 